[The frequency of CTLA-4 gene polymorphism at position 49 exon 1 in children with Hashimoto's thyroiditis].

INTRODUCTION: The cytotoxic T lymphocyte antigen-4 (CTLA-4) is a molecule present on T cells that plays a critical role in the down regulation of antigen-activated immune responses. Its gene polymorphism is a strong candidate gene for conferring susceptibility to thyroid autoimmunity. THE AIM of the study was to analyse the frequency of CTLA-4 exon 1 polymorphism (A49G) in children with Hashimoto's thyroiditis.
MATERIAL AND METHODS: Blood samples from 68 children were analysed: 30 with Hashimoto's thyroiditis and 38 healthy, age-matched controls, mean age: 13.6 years. CTLA-4 exon 1 polymorphism (A49G) was defined by the PCR method and single-strand conformational polymorphism analysis and confirmed by using BbvI enzyme. Statistical analysis was performed using the t- test and Chi-square test.
RESULTS: Polymorphism analysis showed that statistically significant more patients with Hashimoto's thyroiditis were homozygous for G (Ala), and G allele frequency was significant higher than in the control group.
CONCLUSION: The results confirmed the association between CTLA-4 exon 1 polymorphism (A49G) and Hashimoto's thyroiditis in polish children.